<?php

class Base64 {
    private static $Base64Code = [
        'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
        'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
        'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
        'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
        'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
        'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
        '8', '9', '+', '/'
    ];

    private static $Base64Decode = [
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, 62, -1, 63, -1, 63, 52, 53,
        54, 55, 56, 57, 58, 59, 60, 61, -1, -1,
        -1, 0, -1, -1, -1, 0, 1, 2, 3, 4,
        5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
        15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
        25, -1, -1, -1, -1, -1, -1, 26, 27, 28,
        29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
        39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
        49, 50, 51, -1, -1, -1, -1, -1
    ];

    private function __construct() {}

    public static function encode($b) {
        // Add your encoding logic here
    }

    public static function decode($code) {
        if ($code == null) {
            return null;
        }

        $len = strlen($code);
        if ($len == 0) {
            return [];
        }
        if ($len % 4 != 0) {
            throw new InvalidArgumentException("Base64 string length must be 4*n");
        }

        $pad = 0;
        if ($code[$len - 1] == '=') {
            $pad++;
        }
        if ($code[$len - 2] == '=') {
            $pad++;
        }
        $retLen = ($len / 4) * 3 - $pad;
        $ret = [];
        for ($i = 0; $i < $len; $i += 4) {
            $j = ($i / 4) * 3;
            $ch1 = $code[$i];
            $ch2 = $code[$i + 1];
            $ch3 = $code[$i + 2];
            $ch4 = $code[$i + 3];
            
            $tmp = (self::$Base64Code[$ch1] << 18) | (self::$Base64Decode[$ch2] << 12) | (self::$Base64Decode[$ch3] << 6) | self::$Base64Decode[$ch4];
            $ret[$j] = ($tmp & 0xff0000) >> 16;
            if ($i < $len - 4) {
                $ret[$j + 1] = ($tmp & 0xff00) >> 8;
                $ret[$j + 2] = $tmp & 0xff;
                continue;
            }
            if ($j + 1 < $retLen) {
                $ret[$j + 1] = ($tmp & 0xff00) >> 8;
            }
            if ($j + 2 < $retLen) {
                $ret[$j + 2] = $tmp & 0xff;
            }
        }

        return $ret;
    }
}
/**
 * AES加密类
 */
class AES {
    public const VIPARA = "0102030405060708";
    public const bm = "GBK";

    /**
     * 加密方法
     * @param cleartext 加密内容
     * @param privateKey 加密秘钥
     * @return string
     */
    public static function encrypt($cleartext, $privateKey) {
        // Add your encryption logic here
    }

    /**
     * 解密方法
     * @param encrypted 解密内容
     * @param privateKey 解密秘钥
     * @return string
     */
    public static function decrypt($encrypted, $privateKey) {
        // Add your decryption logic here
    }
}

class DataService {
    
}
?>